1. Field of the Invention
This invention relates to a document searching system which enables to search discretionally the documents described by plural different languages (multilingual documents) according to the key word written by the designated language (e.g. native language) and to display the search result by the designated language.
2. Discussion of the Related Art
Recently information must be exchanged between areas having different languages from each other due to the development of communication networks, including the Internet. On the other hand, the information is currently delivered by the use of the electrical memory devices (such as databases, CD-ROMs, etc.). For example, information searching service systems use of databases of documents from science, technology and patents are prevalent.
When documents are searched for by the words used in the documents, it should be noticed that each author of their document may use different words to describe the same meaning, material, matter, etc. Therefore, the search result may miss some expected documents when the searcher fails to designate some alternative words. To prevent such errors, it is known to use a synonym dictionary to automatically collect the words or terms having identical or equivalent meanings and to make a search formula using the collected terms.
When the database to be searched is written in another language from the searcher's native language, the searcher should translate the key words for searching from their native language to that used in the database prior to inputting the search. Such a searching system has been provided in which the search formula input is written by the searcher's native language and then is translated automatically to that used in the database to be searched. The search is then carried out in the database. Such a system is disclosed by Japanese Kokai Patent No. 8-202721 where the search result is translated automatically to the searcher's native language and then displayed.
The documents to be searched are generally text data only, but they are usually supplemented by objects such as drawings, photographs or animations. As for the search result, each object is usually arranged in a designated area and shown together with the text data on the same page. In this case, the object is linked to the text data by assigning a tag with specified function in the document, and such text is referred to as hyper-linked text. SGML and HTML, used in WWW, are two kinds of texts of this type. Such software such as viewers or browsers are generally utilized to interpret and develop the hyper-linked text and then display it.
Such a system may be constructed by combining these techniques mentioned above as follows. When the language used to input the search condition formula is different from that of the documents to be searched, the search condition formula is translated automatically to an equivalent one written in another language so as to include synonyms. The search is then carried out and then the search result is automatically translated to and displayed by the language defined during the input of the search condition formula.